使用rose@qq.com给jack@163.com用户发一封邮件，内容为you jump，i jump.
192.168.182.10 (qq.com)
1、下载mail服务
yum install mailx -y
yum install dovecot -y
yum install cyrus-sasl* -y
vim /etc/postfix/main.cf
vim /etc/dovecot/conf.d/10-mail.conf
vim /etc/dovecot/dovecot.conf
systemctl restart postfix
systemctl restart dovecot
systemctl restart saslauthd
echo 123456 |passwd --stdin rose
chmod 0600 /var/mail/*
192.168.182.20(163.com)
前面同上
在192.168.182.10上配置DNS服务器
yum install bind -y
vim /etc/named.conf
vim /var/named/zone.qq.com
vim /var/named/zone.163.com
vim /etc/resolv.conf
测试
